Difference between revisions of "CSpect:known bugs"

Revision as of 08:24, 5 March 2022

CSpect V2.15.01

sprites: the collision bit is not implemented (intentional for performance reasons)
sprites rendering is not one-scanline-buffer delayed and all changes in sprites affect current scanline (intentional for performance reasons)
(IMPROVED in 2.14.08) modifications to NextRegs done in copper propagate to rendering usually only once per scanline, the state for rendering is sampled around end of right border area before h-blank area (palette changes, X/Y offsets, etc) (intentional for performance reasons)
modifications to NextRegs done by CPU propagate to rendering usually only once per scanline, usually retroactively for whole current scanline (mostly intentional for performance reasons)
Layer2 displays incorrect data for higher banks (maybe the emulator is still emulating the original limits of nextreg $12 and $13, or some other bug, this needs somewhat better test to decipher current behaviour)
blending modes: seems more wrong than 2.14.08, but the test is not comprehensive (HW core 3.1.5 now blends Layer2+ULA in different way (details))
sprites: 4bit relative patterns are incorrect in complex cases
DMA: reading-registers are a bit off (for example status bit5+0 not reset correctly after LOAD, probably few more (but core 3.1.5 also reads bit0 wrongly, so always test own code with all target platforms))
DMA: Zilog mode is not implemented (port 0x0B)
NextZXOS streaming API doesn't work (the initialization of stream fails - rst 8 service 0x86 ; DISK_STRMSTART)
NextReg $02 does not implement soft-reset (and probably also no hard-reset)
sprites: the wrap-around the 512x512 coordinate space is only partially implemented in extreme cases (relative sprite so far from anchor that x8 scale wraps it back onto screen)
default ULA palette after power on (quick boot without NextZXOS) is slightly different
default value: $6E and $6F are supposed to be fixed since V2.12.30, but the SNA test still reads zeroes
some NextRegs read as zero until they are written into first (quick-boot mode with SNA file without full NextZXOS image) (for example regs $03, $12, $13, $14, $42, $4A, $4B, $4C)
NextRegs $09, $34, $41, $8E read incorrectly (reads after certain writes produce wrong value)

not verified in V2.15.01 (but known bugs of older versions, may be still present):

without the full NextZXOS card image the esxdos services are provided by open source CSpect plugin, the implementation is limited and crude - some of the returned values are incorrect/etc, but loading files works.
the initial file-import sequence of CP/M BIOS fails. (get cpm-a.p3d file from somebody with a working clean CP/M installation and copy that into c:/NextZXOS, or use other emulator to create the file)
direct loading of NEX files does not support all combinations of loading-screen type and palette on/off (but V2.12.9 does load more files than V2.12.5, all common ones should work)
sprites: something something about default clipping... just set clip windows explicitly in your SW.

Platform Specific

Mac: Mouse does not work / behaves erratically
Mac: after launch keyboard being irresponsive - try "alt+tab" to other app and back
Linux: the copper disassembly window added in 2.15.01 (ctrl+alt+c) does not draw its content and remains as empty frame (after debugging the plugin: the winform doesn't receive paint messages from the emulator, same winform code running as stand-alone app without emulator does draw in linux)

@@ Line 5: / Line 5: @@
 * (IMPROVED in 2.14.08) modifications to NextRegs done in copper propagate to rendering usually only once per scanline, the state for rendering is sampled around end of right border area before h-blank area (palette changes, X/Y offsets, etc) (intentional for performance reasons)
 * modifications to NextRegs done by CPU propagate to rendering usually only once per scanline, usually retroactively for whole current scanline (mostly intentional for performance reasons)
+* Layer2 displays incorrect data for higher banks (maybe the emulator is still emulating the original limits of nextreg $12 and $13, or some other bug, this needs somewhat better test to decipher current behaviour)
 * blending modes: seems more wrong than 2.14.08, but the test is not comprehensive (HW core 3.1.5 now blends Layer2+ULA in different way ([https://github.com/MrKWatkins/ZXSpectrumNextTests/issues/8 details]))
 * sprites: 4bit relative patterns are incorrect in complex cases
 * DMA: reading-registers are a bit off (for example status bit5+0 not reset correctly after LOAD, probably few more (but core 3.1.5 also reads bit0 wrongly, so always test own code with all target platforms))
 * DMA: Zilog mode is not implemented (port 0x0B)
+* NextZXOS streaming API doesn't work (the initialization of stream fails - rst 8 service 0x86 ; DISK_STRMSTART)
 * NextReg $02 does not implement soft-reset (and probably also no hard-reset)
 * sprites: the wrap-around the 512x512 coordinate space is only partially implemented in extreme cases (relative sprite so far from anchor that x8 scale wraps it back onto screen)
@@ Line 17: / Line 19: @@
 not verified in V2.15.01 (but known bugs of older versions, may be still present):
-* when running without the full NextZXOS card image, the esxdos services are provided by the emulator itself, the implementation is very limited and crude (most of the returned values are incorrect/etc, but loading files works) (should be improved since 2.14.01, since 2.15.01 the esxDOS calls are as separate extension with source available, so may be further verified/improved as you need)
+* without the full NextZXOS card image the esxdos services are provided by open source [https://github.com/mikedailly/CSpect CSpect plugin], the implementation is limited and crude - some of the returned values are incorrect/etc, but loading files works.
 * the initial file-import sequence of CP/M BIOS fails. (get cpm-a.p3d file from somebody with a working clean CP/M installation and copy that into c:/NextZXOS, or use other emulator to create the file)
 * direct loading of NEX files does not support all combinations of loading-screen type and palette on/off (but V2.12.9 does load more files than V2.12.5, all common ones should work)
@@ Line 25: / Line 27: @@
 * Mac: Mouse does not work / behaves erratically
 * Mac: after launch keyboard being irresponsive - try "alt+tab" to other app and back
-* Linux: the copper disassembly window added in 2.15.01 (ctrl+alt+c) does not draw its content and remains as empty frame
+* Linux: the copper disassembly window added in 2.15.01 (ctrl+alt+c) does not draw its content and remains as empty frame (after debugging the plugin: the winform doesn't receive paint messages from the emulator, same winform code running as stand-alone app without emulator does draw in linux)